CN112301242A

CN112301242A - Preparation method of high-strength corrosion-resistant Al-Y-Sc alloy and Al-Y-Sc alloy

Info

Publication number: CN112301242A
Application number: CN202011197584.8A
Authority: CN
Inventors: 冯琴; 黄锴; 韦悦周
Original assignee: Guangxi University
Current assignee: Guangxi University
Priority date: 2020-10-30
Filing date: 2020-10-30
Publication date: 2021-02-02

Abstract

The invention discloses a preparation method of a high-strength corrosion-resistant Al-Y-Sc alloy and the Al-Y-Sc alloy, which comprises the following steps: s1: preparing an alloy ingot: preparing Cu, Sc, Zr, Y, Fe, Cr, Ti and Mn and Al into intermediate alloys, dividing Mg into two parts, smelting the intermediate alloys Al-Cu, Al-Sc, Al-Zr, Al-Y, Al-Fe, Al-Cr, Al-Ti and Al-Mn with pure Zn and high-purity Al, and then sequentially adding a first part of Mg, an Al-Ti-B grain refiner, hexachloroethane and a second part of Mg; obtaining an alloy cast ingot after casting; s2: and carrying out homogenization treatment, solution treatment, quenching, pre-aging, regression and re-aging treatment on the alloy ingot in sequence to obtain the high-strength corrosion-resistant aluminum alloy. The aluminum alloy prepared by the invention has the advantages of high strength, good toughness, excellent thermal stability and fatigue resistance and long service life.

Description

Preparation method of high-strength corrosion-resistant Al-Y-Sc alloy and Al-Y-Sc alloy

Technical Field

The invention belongs to the technical field of aluminum alloy preparation, and particularly relates to a preparation method of a high-strength corrosion-resistant Al-Y-Sc alloy and the Al-Y-Sc alloy.

Background

7055 it belongs to Al-Zn-Mg-Cu series heat-treatable strengthened wrought aluminum alloy, has the characteristics of high specific strength, good hot workability, excellent welding performance and the like, can be used for producing various products such as thick plates, section bars, forgings and the like, and is widely applied to the fields of aviation, navigation, building packaging and chemical industry at present. However, with the recent technological progress, the performance of aluminum alloy sections is more and more difficult to meet the requirements of the existing industrial production and deep space exploration, and meanwhile, although the aluminum alloy research in China has advanced sufficiently, the aluminum alloy sections are still difficult to be arranged in the front of the world, and the basic research on the aspects of the strengthening and toughening theory, the corrosion theory and the like of the 7055 alloy is not deep enough.

The application of rare earth elements in aluminum alloys is a very important research field for a long time, and the rare earth elements can generate a qualitative change effect in cast aluminum alloys, wherein Sc (scandium, atomic number 21, 4 th cycle IIIB group) and Y (yttrium, atomic number 39, 5 th cycle IIIB group) have higher solubility in aluminum alloys than other alloy elements, and gradually become rare earth elements concerned by material researchers.

Disclosure of Invention

The invention aims to solve the technical problem of providing a preparation method of a high-strength corrosion-resistant Al-Y-Sc alloy, and the aluminum alloy prepared by the preparation method has the characteristics of high strength, good toughness, excellent thermal stability and fatigue resistance, long service life and the like.

In order to solve the technical problems, the invention adopts the following technical scheme:

a preparation method of a high-strength corrosion-resistant Al-Y-Sc alloy comprises the following steps:

s1: preparing an alloy ingot: preparing the following raw materials in percentage by mass: the components by mass percent: sc 0.01-0.35%, Cu 2.0-2.6%, Mg 1.8-2.3%, Y0.25%, Zn 7.6-8.4%, Fe 0.15%, Cr 0.04%, Ti 0.06%, Mn 0.05%, Zr 0.08-0.25%, and the balance of Al; preparing Cu, Sc, Zr, Y, Fe, Cr, Ti and Mn and Al into intermediate alloys, dividing Mg into two parts, smelting the intermediate alloys Al-Cu, Al-Sc, Al-Zr, Al-Y, Al-Fe, Al-Cr, Al-Ti and Al-Mn with pure Zn and high-purity Al, adding a first part of Mg into the molten liquid, adding an Al-Ti-B grain refiner after furnace burden is completely melted, standing for 10-20min, and adding hexachloroethane for primary degassing; then adding a second part of Mg, standing for 8-12 min, and then performing secondary degassing; when the temperature rises to 720 ℃, casting is carried out, and alloy cast ingots are obtained after casting;

s2: carrying out homogenization treatment, solution treatment, quenching, pre-aging, regression and re-aging treatment on the alloy ingot in sequence to obtain a high-strength corrosion-resistant aluminum alloy;

the homogenization treatment temperature is 465 ℃, and the heat preservation time is 24 hours;

the solution treatment temperature is 455 ℃ and the time is 2 hours;

the quenching temperature is room temperature, and the quenching transfer time is not more than 10 s;

the preaging temperature is 120 ℃, and the time is 12 h;

the regression temperature is 180 ℃, and the time is 15 min;

the reaging temperature is 120 ℃, and the time is 24 h.

Further, in step S1, the Mg adding method is as follows: wrapping Mg with aluminum foil, pressing into the bottom of the melt with a bell jar, and taking out the bell jar after the Mg is completely melted.

Further, in step S1, the casting method is: preparing a Cu mould, heating the Cu mould, slowly injecting Al alloy liquid into the Cu mould, and controlling the continuous flow in the casting process until the Al alloy liquid is completely cast into the Cu mould.

Further, the Cu die is heated to 450-550 ℃.

Further, in the step S1, the mass ratio of the first portion of Mg to the second portion of Mg is 7: 3.

Further, in the step S1, the addition amount of the Al-Ti-B grain refiner is 0.2-0.6% of the weight of the furnace burden.

Further, in the step S1, the addition amount of the hexachloroethane subjected to primary degassing is 2-6% of the weight of the furnace burden.

Further, in the step S1, the addition amount of the secondary degassing hexachloroethane is 1-3% of the weight of the furnace burden.

Further, in the above-mentioned step S2, the temperature increase rate of the homogenization treatment is 2 ℃/min.

An Al-Y-Sc alloy prepared according to the high-strength corrosion-resistant preparation method.

The invention has the following beneficial effects:

1. in the raw materials of the Al-Y-Sc alloy, the strengthening mechanism of the proper amount of Sc on the aluminum alloy is that Sc and Al elements have micro-alloying action and dispersed Al₃The Sc particles have strong strengthening effects of fine grain strengthening, substructure strengthening, dispersion strengthening, coherent strengthening and the like on the alloy; sc element is distributed along dendritic crystal and crystal boundary to form a net structure, so that the crystal boundary strength and creep resistance are improved, and cracks are not easy to expand; in addition, Sc element can be added to reduce the hot cracking tendency in the alloy welding process caused by the addition of Cu element, and the strength of the alloy is obviously improved.

2. In the raw materials of the Al-Y-Sc alloy, a proper amount of rare earth element Y has obvious refining effect on the crystal grains of the alloy as-cast structure, thereby effectively improving the mechanical property of the material; y also has an improvement effect on the hot cracking tendency of the Cu element in the welding process of the raw material, improves the tensile strength, the heat resistance, the shock resistance and the corrosion resistance of the aluminum alloy material, can improve the conductivity of the aluminum alloy material and improve the weldability, does not influence the conductivity of the aluminum alloy material, thereby obviously improving the strength and the welding performance of the aluminum alloy material, playing a certain role in purifying and removing hydrogen and improving the tissue structure of the aluminum alloy; in addition, Y and Al, Cu and the like form a dispersed high-melting-point compound, and the thermal stability and heat resistance of the aluminum alloy bar are improved.

3. In the raw materials of the Al-Y-Sc alloy, a proper amount of Zr can improve the fracture toughness of the alloy to a certain extent, and the Zr can improve the hardenability and weldability of the aluminum alloy due to smaller quenching sensitivity; zr also has stronger corrosion resistance, can react with non-metal elements and a plurality of metal elements at high temperature to generate solid solution compounds, is very stable and can improve the corrosion resistance of the whole alloy; in addition, the price of Zr is less than one percent of that of Sc, and expensive Sc is replaced by Zr, so that the raw material cost can be greatly reduced.

4. The invention forms a special internal structure by reasonably adjusting the proportioning relationship among the components, and effectively improves the internal structureThe mechanical strength of the aluminum alloy material is improved, and the problem of low strength of the aluminum alloy material is solved; the Al-Y-Sc alloy material has higher mechanical strength and corrosion resistance, good comprehensive performance and high strength and toughness, as shown in example 4, the tensile strength can reach 395.8MPa, the elongation can reach 14.2 percent, the conductivity can reach 33.8IACS, the corrosion resistance is good, and the corrosion current density is reduced to 1.26 multiplied by 10^-7A/cm²The corrosion speed is slowed down; the aluminum alloy material crystal grain prepared by the raw material proportion and the preparation method has higher uniformity and smaller grain diameter, and the generation of defects is reduced; meanwhile, the raw material cost is reasonably controlled, the market competitiveness is strong, and the rigorous requirements of modern technological development on high-performance aluminum alloy materials are well met.

5. As can be seen from the data in Table 1, Sc, Zr and Y all have the effect of improving the tensile strength, elongation and corrosion resistance of the aluminum alloy material, but the effect of Sc, Zr and Y acting together is better than the superposition of the effects of Sc, Zr and Y acting alone respectively, so that Sc, Zr and Y have the effect of synergistically improving the tensile strength, elongation and corrosion resistance.

Drawings

FIG. 1 is a photograph of OM of a sample prepared in example 2 of the present invention;

FIG. 2 is a photograph of OM for the sample prepared in comparative example 1;

FIG. 3 is a photograph of OM for the sample prepared in comparative 2;

fig. 4 is a photograph of OM for the sample prepared in comparison 3;

fig. 5 is a photograph of OM for the sample prepared in comparative example 4.

Detailed Description

In order to facilitate a better understanding of the invention, the following examples are given to illustrate, but not to limit the scope of the invention.

The present invention is illustrated by the following more specific examples.

Example 1

s1: preparing an alloy ingot: preparing 500g of raw materials according to the following mass percentages: the components by mass percent: sc 0.01%, Cu 2.0%, Mg 1.8%, Y0.25%, Zn 7.6%, Fe 0.15%, Cr 0.04%, Ti 0.06%, Mn 0.05%, Zr 0.08%, and the balance of Al; preparing intermediate alloys from Cu, Sc, Zr, Y, Fe, Cr, Ti and Mn and Al, dividing Mg into two parts according to the mass ratio of 7:3, smelting the intermediate alloys Al-Cu, Al-Sc, Al-Zr, Al-Y, Al-Fe, Al-Cr, Al-Ti and Al-Mn with pure Zn and high-purity Al, wrapping the first part of Mg with an aluminum foil, covering and pressing the first part of Mg into the bottom of a molten solution with a bell jar, taking out the bell jar after the materials are completely molten, adding 1g of Al-Ti-B grain refiner after the furnace burden is completely molten, standing for 10min, adding 10g of hexachloroethane, and degassing for one time; then wrapping the second part of Mg with aluminum foil, covering the second part of Mg with a bell jar, pressing into the bottom of the molten liquid, taking out the bell jar after the Mg is completely melted, standing for 8min, and adding 5g of hexachloroethane again for secondary degassing; when the temperature rises to 720 ℃, casting is carried out, the Al alloy liquid is slowly injected into a Cu die which is heated to 450 ℃ in advance, and the flow is not interrupted in the casting process until the Al alloy liquid is completely cast into the Cu die, so that an alloy cast ingot is obtained;

s2: carrying out homogenization treatment, solution treatment, quenching, pre-aging, regression and re-aging treatment on the alloy ingot in sequence, wherein the temperature rise rate of the homogenization treatment is 2 ℃/min, the temperature is raised to 465 ℃, and the heat preservation time is 24 h; the solution treatment temperature is 455 ℃ and the time is 2 hours; the quenching temperature is room temperature, and the quenching transfer time is 9 s; the preaging temperature is 120 ℃, and the time is 12 h; the regression temperature is 180 ℃ and the time is 15 min; the reaging temperature is 120 ℃, and the time is 24 h; obtaining the high-strength corrosion-resistant aluminum alloy.

Example 2

s1: preparing an alloy ingot: preparing 500g of raw materials according to the following mass percentages: the components by mass percent: sc 0.25%, Cu 2.3%, Mg 2.0%, Y0.25%, Zn 8.0%, Fe 0.15%, Cr 0.04%, Ti 0.06%, Mn 0.05%, Zr 0.15%, and the balance of Al; preparing intermediate alloys from Cu, Sc, Zr, Y, Fe, Cr, Ti and Mn and Al, dividing Mg into two parts according to the mass ratio of 7:3, smelting the intermediate alloys Al-Cu, Al-Sc, Al-Zr, Al-Y, Al-Fe, Al-Cr, Al-Ti and Al-Mn with pure Zn and high-purity Al, wrapping the first part of Mg with an aluminum foil, covering and pressing the first part of Mg into the bottom of a molten solution with a bell jar, taking out the bell jar after the materials are completely molten, adding 2g of Al-Ti-B grain refiner after the furnace burden is completely molten, standing for 15min, adding 20g of hexachloroethane, and degassing for one time; then wrapping the second part of Mg with aluminum foil, covering the second part of Mg with a bell jar, pressing into the bottom of the molten liquid, taking out the bell jar after the Mg is completely melted, standing for 10min, and adding 10g of hexachloroethane again for secondary degassing; when the temperature rises to 720 ℃, casting is carried out, Al alloy liquid is slowly injected into a Cu die which is heated to 500 ℃ in advance, and the flow is not interrupted in the casting process until the Al alloy liquid is completely cast into the Cu die, so that an alloy cast ingot is obtained;

s2: carrying out homogenization treatment, solution treatment, quenching, pre-aging, regression and re-aging treatment on the alloy ingot in sequence, wherein the temperature rise rate of the homogenization treatment is 2 ℃/min, the temperature is raised to 465 ℃, and the heat preservation time is 24 h; the solution treatment temperature is 455 ℃ and the time is 2 hours; the quenching temperature is room temperature, and the quenching transfer time is 8 s; the preaging temperature is 120 ℃, and the time is 12 h; the regression temperature is 180 ℃ and the time is 15 min; the reaging temperature is 120 ℃, and the time is 24 h; obtaining the high-strength corrosion-resistant aluminum alloy.

Example 3

s1: preparing an alloy ingot: preparing 500g of raw materials according to the following mass percentages: the components by mass percent: sc 0.35%, Cu 2.6%, Mg 2.3%, Y0.25%, Zn 8.4%, Fe 0.15%, Cr 0.04%, Ti 0.06%, Mn 0.05%, Zr 0.25%, and the balance of Al; preparing Cu, Sc, Zr, Y, Fe, Cr, Ti and Mn and Al, dividing Mg into two parts according to the mass ratio of 7:3, smelting intermediate alloys Al-Cu, Al-Sc, Al-Zr, Al-Y, Al-Fe, Al-Cr, Al-Ti and Al-Mn with pure Zn and high-purity Al, wrapping the first part of Mg with an aluminum foil, covering and pressing the first part of Mg at the bottom of a melt with a bell jar, taking out the bell jar after the materials are completely melted, adding 3g of Al-Ti-B grain refiner after the furnace burden is completely melted, standing for 10-20min, adding 30g of hexachloroethane, and degassing for one time; then wrapping the second part of Mg with aluminum foil, covering the second part of Mg with a bell jar, pressing into the bottom of the molten liquid, taking out the bell jar after the Mg is completely melted, standing for 12min, and adding 15g of hexachloroethane again for secondary degassing; when the temperature rises to 720 ℃, casting is carried out, Al alloy liquid is slowly injected into a Cu die which is heated to 500 ℃ in advance, and the flow is not interrupted in the casting process until the Al alloy liquid is completely cast into the Cu die, so that an alloy cast ingot is obtained;

s2: carrying out homogenization treatment, solution treatment, quenching, pre-aging, regression and re-aging treatment on the alloy ingot in sequence, wherein the temperature rise rate of the homogenization treatment is 2 ℃/min, the temperature is raised to 465 ℃, and the heat preservation time is 24 h; the solution treatment temperature is 455 ℃ and the time is 2 hours; the quenching temperature is room temperature, and the quenching transfer time is 7 s; the preaging temperature is 120 ℃, and the time is 12 h; the regression temperature is 180 ℃ and the time is 15 min; the reaging temperature is 120 ℃, and the time is 24 h; obtaining the high-strength corrosion-resistant aluminum alloy.

Comparative example 1

Basically the same as example 2 except that the raw materials for preparing the aluminum alloy lack Sc, Zr, Y.

Comparative example 2

Substantially the same as in example 2, except that the starting material for the preparation of the aluminum alloy lacks Sc.

Comparative example 3

Substantially the same as in example 2, except that Zr was absent from the starting materials for the preparation of the aluminum alloy.

Comparative example 4

Substantially the same as in example 2 except that Y is absent from the starting material for the preparation of the aluminum alloy.

Example 4

1. Measurement of mechanical Strength of aluminum alloy

On the basis of the same plate area and the same plate clamping distance, mechanical strength tests were performed on the plates prepared in examples 1 to 3 and ratios 1 to 4 by using a QT-1136PC Universal Material testing machine (Guangdong Gaotai detection Instrument Co., Ltd.). The aluminum alloys prepared in examples 1 to 3 and comparative examples 1 to 4 were used as anode electrodes, immersed in 3.5 mass% NaCl aqueous solution, and tested for corrosion resistance using the CHI-660 electrochemical workstation.

The results are shown in Table 1.

TABLE 1 mechanical Strength test results of the respective aluminum alloy materials

Material	Tensile strength/MPa	Elongation/percent	conductivity/IACS	Corrosion current density/A/cm²
					Example 1	366.9	11.6	33.6	7.50×10^-7
Example 2	395.8	14.2	33.8	1.26×10^-7
					Example 3	391.3	13.8	33.7	1.32×10^-7
Comparative example 1	321.8	9.4	30.3	22.79×10^-7
					Comparative example 2	365.3	11.5	33.2	7.53×10^-7
Comparative example 3	383.0	13.5	32.0	8.22×10^-7
					Comparative example 4	371.9	13.3	33.1	7.66×10^-7

As can be seen from Table 1: example 2 is the most preferred example;

(1) compared with the example 2, on the basis of the same other preparation conditions, the raw materials for preparing the aluminum alloy in the comparative example 1 lack Sc, Zr and Y, the tensile strength of the prepared aluminum alloy is reduced by 74.0MPa, the elongation is reduced by 4.8%, the conductivity is reduced by 3.42IACS, and the corrosion current density is improved by 21.53A/cm²(ii) a Compared with the comparative example 2, the raw material for preparing the aluminum alloy is lack of Sc, the tensile strength of the prepared aluminum alloy is reduced by 30.5MPa, the elongation is reduced by 2.7 percent, the conductivity is reduced by 0.6IACS, and the corrosion current density is improved by 6.27 multiplied by 10^-7A/cm²(ii) a The raw materials for preparing the aluminum alloy in the comparative example 3 lack Zr, the tensile strength of the prepared aluminum alloy is reduced by 12.8MPa, the elongation is reduced by 1.8 percent, the conductivity is reduced by 0.7IACS, and the corrosion current density is improved by 6.96 multiplied by 10^-7A/cm²(ii) a The raw material for preparing the aluminum alloy in the comparative example 4 is lack of Y, the tensile strength of the prepared aluminum alloy is reduced by 23.9MPa, the elongation is reduced by 0.9 percent, the conductivity is reduced by 0.7IACS, and the corrosion current density is improved by 6.4 multiplied by 10^-7A/cm²。

(2) As is clear from (1), in comparison with example 2, when Sc, Zr and Y were used together, the tensile strength was improved by 74.0MPa, the elongation was improved by 4.8%, the electrical conductivity was improved by 3.42IACS, and the corrosion current density was reduced by 21.53X 10^-7A/cm²(ii) a When Sc is used alone, the tensile strength can be improved by 30.5MPa, the elongation can be improved by 2.7%, the conductivity can be reduced by 0.6IACS, and the corrosion current density can be improved by 6.27 multiplied by 10^-7A/cm²(ii) a When Zr acts alone, the tensile strength can be improved by 12.8MPa, the elongation rate is improved by 1.8 percent, the electric conductivity is reduced by 0.7IACS, and the corrosion current density is improved by 6.96 multiplied by 10^-7A/cm²(ii) a When Y acts alone, the tensile strength can be improved by 23.9MPa, the elongation can be improved by 0.9 percent, the conductivity can be reduced by 0.7IACS, and the corrosion current density can be improved by 6.4 multiplied by 10^-7A/cm²(ii) a Therefore, the effect of improving the tensile strength when Sc, Zr and Y act together is increased compared with the effect when Sc, Zr and Y act separately: [74.0- (30.5+12.8+23.9)]10.1% > 10% of ÷ (30.5+12.8+23.9) × 100%; the effect of improving the bending strength when Sc, Zr and Y act together is increased compared with the effect when Sc, Zr and Y act separately: [4.8- (2.7+0.7+0.9)]2.7+0.7+0.9) × 100% >, 11.6% > 10%; the effect of improving the conductivity when Sc, Zr and Y act together is increased compared with the effect when Sc, Zr and Y act separately: [3.42- (0.6+1.8+0.7)]10.3% > 10% of ÷ (0.6+1.8+0.7) × 100%; the effect of reducing the corrosion current density when Sc, Zr and Y act together is increased compared with the effect when Sc, Zr and Y act separately: [4.8- (2.7+0.7+0.9)]2.7+0.7+0.9) × 100% >, 11.6% > 10%; the effect of improving the conductivity when Sc, Zr and Y act together is increased compared with the effect when Sc, Zr and Y act separately: [21.60×10^-7-(6.27×10^-7+6.96×10^-7+6.4×10^-7)]÷(6.27×10^-7+6.96×10^-7+6.4×10^-7) X 100% ═ 10.0%. Therefore, when Sc, Zr and Y are used together, a synergistic effect is generated, the tensile strength, the elongation and the conductivity of the aluminum alloy are synergistically improved, and the electro-corrosion density is synergistically reduced.

(3) As can be seen from FIGS. 1 to 5, the crystal grains of the sample prepared in example 2 of the present invention are more uniform than those of the samples prepared in comparative examples 1 to 4, the crystal grain size is also refined, and the defects generated thereby are significantly less than those of the samples prepared in comparative examples 1 to 4.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. The preparation method of the high-strength corrosion-resistant Al-Y-Sc alloy is characterized by comprising the following steps of:

s1: preparing an alloy ingot: preparing the following raw materials in percentage by mass: 0.01 to 0.35 percent of Sc, 2.0 to 2.6 percent of Cu2.8 to 2.3 percent of Mg, 0.25 percent of Y, 7.6 to 8.4 percent of Zn, 0.15 percent of Fe, 0.04 percent of Cr, 0.06 percent of Ti, 0.05 percent of Mn, 0.08 to 0.25 percent of Zr and the balance of Al; preparing Cu, Sc, Zr, Y, Fe, Cr, Ti and Mn and Al into intermediate alloys, dividing Mg into two parts, smelting the intermediate alloys Al-Cu, Al-Sc, Al-Zr, Al-Y, Al-Fe, Al-Cr, Al-Ti and Al-Mn with pure Zn and high-purity Al, adding a first part of Mg into the molten liquid, adding an Al-Ti-B grain refiner after furnace burden is completely melted, standing for 10-20min, and adding hexachloroethane for primary degassing; then adding a second part of Mg, standing for 8-12 min, and then performing secondary degassing; when the temperature rises to 720 ℃, casting is carried out, and alloy cast ingots are obtained after casting;

the solution treatment temperature is 455 ℃ and the time is 2 hours;

the preaging temperature is 120 ℃, and the time is 12 h;

the regression temperature is 180 ℃, and the time is 15 min;

the reaging temperature is 120 ℃, and the time is 24 h.

2. The method for preparing a high-strength corrosion-resistant Al-Y-Sc alloy according to claim 1, wherein in step S1, Mg is added in a manner that: wrapping Mg with aluminum foil, pressing into the bottom of the melt with a bell jar, and taking out the bell jar after the Mg is completely melted.

3. The method for preparing a high-strength corrosion-resistant Al-Y-Sc alloy according to claim 1, wherein in step S1, the casting method is as follows: preparing a Cu mould, heating the Cu mould, slowly injecting Al alloy liquid into the Cu mould, and controlling the continuous flow in the casting process until the Al alloy liquid is completely cast into the Cu mould.

4. The method of preparing a high strength corrosion resistant Al-Y-Sc alloy as recited in claim 3, further comprising: and heating the Cu die to 450-550 ℃.

5. The method of preparing a high strength corrosion resistant Al-Y-Sc alloy as recited in claim 1, further comprising: in the step S1, the mass ratio of the first Mg part to the second Mg part is 7: 3.

6. The method of preparing a high strength corrosion resistant Al-Y-Sc alloy as recited in claim 1, further comprising: in the step S1, the addition amount of the Al-Ti-B grain refiner is 0.2-0.6% of the weight of the furnace burden.

7. The method for preparing the high-strength corrosion-resistant Al-Y-Sc alloy according to claim 1, wherein: in the step S1, the addition amount of the hexachloroethane subjected to primary degassing is 2-6% of the weight of the furnace burden.

8. The method of preparing a high strength corrosion resistant Al-Y-Sc alloy as recited in claim 1, further comprising: in the step S1, the addition amount of the secondary degassing hexachloroethane is 1-3% of the weight of the furnace burden.

9. The method of preparing a high strength corrosion resistant Al-Y-Sc alloy as recited in claim 1, further comprising: in step S2, the temperature increase rate of the homogenization treatment is 2 ℃/min.

10. An Al-Y-Sc alloy prepared by the high strength corrosion resistant method of preparation according to any one of claims 1 to 9.